CN102927919A - Measurement device for tangent circle diameter of fuel nozzle of power station boiler and measurement method thereof - Google Patents

Abstract

The invention discloses a measuring device and a measuring method for the tangential circle diameter of a power station boiler burner. The measuring device is mainly composed of a rectangular steel plate, an infrared generator and a level. Among them, slots are processed on the longitudinal centerline and the lower left position of the steel plate for fixed installation of the infrared generator and level. The target distance can be accurately measured by using the characteristics of infrared visibility and positioning, and the theoretical tangent circle diameter can be obtained through relatively simple geometric calculation. The measuring method has simple device, few measuring parameters and high accuracy. At present, the device and calculation method have been successfully applied to the theoretical tangent circle measurement in the furnace of the generator sets of many thermal power companies, and the operation data results have proved that the measurement data is accurate and reliable.

Description

Measuring device and method for tangential circle diameter of power plant boiler burner

technical field

The invention relates to a measuring device and a measuring method for the tangential circle diameter of a power station boiler burner.

Background technique

The theoretical tangential circle diameter of the burner of a utility boiler is an important design parameter for the safe and economical operation of a thermal power unit.

The larger diameter of the theoretical tangent circle has the following advantages for combustion in the furnace: 1) The rotational momentum increases and the disturbance is strong, which is beneficial to the burnout of the fuel; 2) The center of the flame is close to the primary tuyere, and the ignition conditions of the pulverized coal are good; 3) The fullness of the furnace is good, and the utilization rate of the furnace is high, which enhances the heat transfer effect of the water-cooled wall.

However, when the theoretical tangent circle diameter of the burner is too large, the problems are as follows: 1) The actual tangent circle diameter increases, the wind speed of the wall increases, and the high-temperature flue gas is easy to stick to the wall and cause coking; 2) The burner is easy to deform, exceed 3) The weak wind area in the center of the furnace is too large, which reduces the utilization rate of the furnace volume; 4) Due to the high initial swirl intensity and the reduced attenuation speed, the residual torsion of the furnace outlet increases, which is very important to prevent the deviation of the furnace outlet smoke temperature unfavorable.

When the theoretical tangential circle diameter of the burner is reduced, it will have an adverse effect on the combustion stability. For comprehensive comparison, it is necessary to determine the appropriate tangential circle diameter for different coal types and different furnace types. At this stage, unit safety accidents emerge in endlessly due to inappropriate design or adjustment of the tangent circle diameter, which has brought huge hidden dangers to the safe production of electric power enterprises.

For a long time, the traditional wire-drawing method has been used for the theoretical tangential circle diameter. This method needs to hang a vertical wire on the furnace roof and pull the wire on the measurement plane. The workload is large; there are many influencing factors, the measurement data is rough, and the error is large. A simple and accurate method of measurement emerges. The paper "Experimental Research on Calibration of Burners Using Laser Technology" mentioned a method of measuring the distance between the vertical and horizontal laser beams to obtain the diameter of the imaginary tangential circle. 2) It is necessary to measure the distance between two laser beams in different directions, which is difficult to operate and has a large cumulative error; 3) The measuring equipment is complex and the workload is large.

Therefore, inventing a simple and reliable equipment and method to accurately measure the theoretical tangent circle diameter in the furnace has positive guiding significance for the safe, stable and economical operation of the unit.

Contents of the invention

The object of the present invention is to solve the above problems, and provide a device and method for measuring the tangential circle diameter of the burner of a utility boiler, which has the advantages of simple device, few measurement parameters and high accuracy.

In order to achieve the above object, the present invention adopts the following technical solutions:

A power plant boiler burner tangential diameter measuring device, comprising a rectangular steel plate, an infrared generator, and a level; the infrared generator is installed in a slot on the longitudinal centerline of the surface of the rectangular steel plate; the level is installed on the surface of the rectangular steel plate in the corner slot.

The method for measuring the tangential circle diameter measuring device of the burner of a power plant boiler is divided into the following specific steps:

Step (1), placing the power plant boiler burner tangential diameter measuring device in the burner cylinder; the burner cylinder is placed at the four corners of the furnace;

Step (2), turn on the infrared generator;

Step (3), measure the distance between the infrared falling point and the diagonal wall line;

In step (4), the rectangular coordinate system of the furnace section is established and an auxiliary line is made, and the theoretical tangential circle diameter is obtained through calculation according to the known furnace size and measurement data.

The rectangular steel plate in the step (1) is placed horizontally in the cylinder of the burner, and there is no gap between the edge of the rectangular steel plate and the inner wall of the cylinder.

The infrared ray emitted by the infrared ray generator in the step (2) coincides with the longitudinal midline of the rectangular steel plate.

The calculation method of the step (4) is:

The infrared rays emitted by the infrared generator start from a corner of the furnace, and the infrared rays pass through the point E to the opposite furnace wall N, and measure the length of the target distance MN of the opposite furnace wall (see Figure 2). Then, according to the known furnace size and the only measurement data MN, through a series of calculations, the theoretical tangential diameter of the burner is obtained. The specific solution method is:

Known furnace size and measurement data: furnace width AB=CD=a, furnace length BC=DA=b, measurement data MN=c, four corners are congruent equilateral right-angled triangles, and the length of its right-angled side BM=BG=d, E , F, and H are the midpoints of the triangular line respectively, through O, P two points make a perpendicular line of OR, PQ side, through H, P, F three points make a perpendicular line of BC side.

Find the theoretical tangent circle diameter 2OR, where OR is the radius of the theoretical tangent circle of the burner.

The specific calculation method is as follows:

Establish a Cartesian coordinate system with point E as the origin

Through calculation, the coordinates of the two points N and O can be obtained as

The equation of the line passing through the two points E and N is $(b-c-\frac{3d}{2})x-(a-\frac{d}{2})\mathrm{the\; y}=0---\left(1\right)$

x and y are independent variables. Then, the theoretical tangent circle diameter is

$\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; OR</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; |</span><span\; class="notranslate">\; /</span>\sqrt{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

The diameter of the theoretical tangent circle can also be obtained by using triangle similarity, as

$\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; OR</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; EO</span>}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; PQ</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; EP</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; [</span>\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="d"\; filenames="HDA00002325071900011.png"\; state="\{\{state\}\}">d</figure-callout></span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="d"\; filenames="HDA00002325071900011.png"\; state="\{\{state\}\}">d</figure-callout></span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>$

(3)

$\sqrt{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; [</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; d</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; b</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; c</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

The beneficial effect of the invention is that the appropriate tangential circle diameter is provided for different coal types and different furnace types, the device is simple, the measurement parameters are few, and the accuracy is high. Reduce coking accidents caused by high-temperature flue gas sticking to the wall; reduce burner accidents that are easily deformed and overheated; make the weak wind area in the center of the furnace suitable, and increase the utilization rate of the furnace volume; The speed decreases, resulting in the increase of the residual torsion of the furnace outlet and the adverse effects of the deviation of the smoke temperature at the furnace outlet. The geometric center of the furnace plane is easy to locate accurately; there is no need to measure the distance between multiple laser beams, the operation is simple, the measuring equipment is simple, and the workload is small.

Description of drawings

Figure 1 is a schematic diagram of the measuring device;

Fig. 2 is the schematic diagram of furnace section and calculation method;

Wherein, 1. Rectangular steel plate, 2. Infrared ray generator, 3. Spirit level, 4. Infrared ray.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, a device for measuring the tangential circle diameter of a power plant boiler burner includes a rectangular steel plate 1, an infrared generator 2, and a level 3; the infrared generator 2 is installed in a slot on the longitudinal centerline of the rectangular steel plate 1 Middle; the level 3 is installed in a corner of the surface of the rectangular steel plate 1 in the groove. The infrared ray 4 emitted by the infrared ray generator 2 coincides with the longitudinal midline of the rectangular steel plate 1 .

The 3# unit of a power generation company had serious coking phenomenon, and two coke loss and fire extinguishing accidents occurred in a relatively short period of time, which seriously threatened the safety of the unit and power grid equipment. The company immediately set up an expert group to analyze the cause of the accident. After discussion, the expert group proposed five possible reasons for the boiler operation mode and equipment structure. High, high-temperature flue gas with coal powder and ash sticking to the wall causes coking. In order to thoroughly understand the cause of the accident, the maintenance headquarters decided to measure the theoretical tangent circle diameter of the burner in the furnace during the minor maintenance of the unit.

It is known that the size of the furnace is a=10240mm, b=11360mm, d=280mm, the target length c=395mm is measured on the spot, and the theoretical tangential circle diameter of the burner is calculated.

Substituting the specific values of a, b, c, and d into formula (2) (3) respectively, it can be obtained

$\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; OR</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; |</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 11360</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 395</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; 10240</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 10240</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; 11360</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; |</span><span\; class="notranslate">\; /</span>$

$\sqrt{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 11360</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 395</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 10240</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 471.2</span>}\mathrm{<span\; class="notranslate">\; mm</span>}$

$\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; OR</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; [</span>\frac{\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 395</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 11360</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 395</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 10240</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 280</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 10240</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 280</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>$

$\sqrt{{(10240-280)}^2+{[(10240-280)*(11360-395-\frac{3*280}{2})/(10240-\frac{280}{2})}^2}=471.2\mathrm{mm}$ The theoretical tangent circle diameter of the burner designed by the boiler manufacturer is 400-450mm, and the measured value is obviously larger than the design value, which preliminarily verifies the inference of the cause of the accident before the measurement. Therefore, during the maintenance period, the construction personnel made appropriate adjustments to the angle of the burner, so that the theoretical tangent circle diameter was stabilized at 415mm.

The 3# unit has been running safely for four months since it was started, and the coking situation in the furnace has been significantly improved.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, those skilled in the art do not need to pay creative work Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (5)

1. a station boiler burner tangential circle diameter measurement mechanism is characterized in that, comprises rectangular steel plates, infrared generator, level meter; Described infrared generator is installed in the draw-in groove of rectangular steel plates surface longitudinal center line; Described level meter is installed in one jiao the draw-in groove on rectangular steel plates surface.

2. a kind of station boiler burner tangential circle diameter measurement mechanism as claimed in claim 1 is characterized in that, described rectangular steel plates is horizontal positioned in the burner cylinder, and rectangular steel plates edge and cylinder inner wall are seamless.

3. a kind of station boiler burner tangential circle diameter measurement mechanism as claimed in claim 1 is characterized in that, the infrared ray that described infrared generator sends overlaps with the rectangular steel plates longitudinal midline.

4. such as the measuring method of claim 1 or 2 or 3 described a kind of station boiler burner tangential circle diameter measurement mechanisms, it is characterized in that, described concrete steps are as follows:

Step (1) places station boiler burner tangential circle diameter measurement mechanism in the burner cylinder; Described burner cylinder is positioned over four angles of burner hearth;

Step (2) is opened infrared generator;

Step (3), the distance of measurement infrared ray drop point and diagonal angle wall line;

Step (4) is set up the section of burner hearth rectangular coordinate system and is made boost line, according to known size of burner hearth and measurement data, tries to achieve theoretical tangential circle diameter by calculating.

5. a kind of station boiler burner tangential circle diameter measuring method as claimed in claim 2 is characterized in that, the computing method of described step (4) are:

The infrared ray that infrared generator sends is from burner hearth one angle, infrared ray is mapped on the furnace wall N on opposite through an E, measure the length of the target range MN of opposite furnace wall, then, according to known size of burner hearth and unique measurement data MN, by a series of calculating, try to achieve the theoretical tangential circle diameter of burner, concrete method for solving is:

Known size of burner hearth and measurement data: furnace width AB=CD=a, burner hearth length BC=DA=b, measurement data MN=c, four jiaos is congruent equilateral right-angle triangle, its right-angle side length BM=BG=d, E, F, H are respectively the mid point of triangle line, cross the vertical line that O, 2 of P do OR, PQ limit, cross H, P, 3 vertical lines of doing the BC limit of F, ask theoretical tangential circle diameter 2OR;

Circular is as follows:

Set up rectangular coordinate system take an E as initial point

Be respectively by the coordinate that calculates 2 of N, O

Straight-line equation by 2 of E, N is $(b-c-\frac{3d}{2})x-(a-\frac{d}{2})y=0---\left(1\right)$

So, theoretical tangential circle diameter is

$2\mathrm{OR}=2|(b-c-\frac{3d}{2})*\left(\frac{a-d}{2}\right)-(a-\frac{d}{2})*\left(\frac{b-d}{2}\right)|/\sqrt{{(b-c-\frac{3d}{2})}^2+{(a-\frac{d}{2})}^2}---\left(2\right)$

Adopt that triangle is similar tries to achieve theoretical tangential circle diameter, for

$2\mathrm{OR}=2\mathrm{EO}*\mathrm{PQ}/\mathrm{EP}=[\frac{d}{2}+c+\frac{d}{2}*(b-c-\frac{3d}{2})/(a-\frac{d}{2})]*(a-d)/$

（3）

$\sqrt{{(a-d)}^2+{[(a-d)*(b-c-\frac{3d}{2})/(a-\frac{d}{2})]}^2}.$

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